Metals for photo etching are produced in the following forms: flat sheets, coil, and blanks cut to size.
Metals most commonly used as flat sheets are aluminum, annealed stainless steel, copper, and brass. Nickel, beryllium copper, and phosphor bronze are normally supplied in coil stock.
Often flat sheet metal will be coated to protect the surface during shipment. The coating is then removed before the metal is photo etched, during the cleaning process.
The photo etching process does not affect the mechanical properties of the metal. Fully annealed metals remain fully annealed. Likewise, the hardness of hardened metals is not affected by photo chemical etching process.